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A 500 W SOFC stack provided by Topsoe Fuel Cells A/S was run with reformed diesel fuel for 1,200 h. Diesel fuel used was Swedish Environmental Class 1 containing <10 ppm of sulfur. The fuel was reformed with an autothermal reformer (ATR). The reformer consisted of a mixing chamber and a reactor chamber containing a noble metal catalyst provided by SüdChemie. The reformer used the diesel fuel without any pre-treatment such as sulfur adsorbent. The reformer unit was able to achieve high conversion of reactants with only ppm levels of higher hydrocarbons at the reformer outlet. Particulate emissions of the reformer were measured to be 30 μg m-3, a very low value even below daily exposure limits in ambient air set by the European Comission directives. The stack was first run with 3% humidified H2 + N2 fuel to obtain baseline performance and then switched to reformate. Diesel reformate was found not to induce significantly more long-term degradation on the stack compared to hydrogen case. However, an initial degradation of about 20 mV cell-1 was observed during the first 150 h on diesel fuel reformate. This could be an indication of a poisoning mechanism taking place, but needs further research to be verified. [ABSTRACT FROM AUTHOR]

The performance and current distribution of a free-breathing polymer electrolyte membrane fuel cell (PEMFC) was studied experimentally in a climate chamber, in which temperature and relative humidity were controlled. The performance was studied by simulating ambient conditions in the temperature range 10 to 40 °C. The current distribution was measured with a segmented current collector. The results indicated that the operating conditions have a significant effect on the performance of the fuel cell. it was observed that a temperature gradient between the fuel cell and air is needed to achieve efficient oxygen transport to the electrode. Furthermore, varying the air humidity resulted in major changes in the mass diffusion overpotential at higher temperatures. [ABSTRACT FROM AUTHOR]

A single-site, randomized clinical trial was designed to determine the efficacy of regular home use of Lumoral ® dual-light antibacterial aPDT in periodontitis patients. For the study, 200 patients were randomized to receive non-surgical periodontal treatment (NSPT), including standardized hygiene instructions and electric toothbrush, scaling and root planing, or NSPT with adjunctive Lumoral ® treatment. A complete clinical intraoral examination was conducted in the beginning, at three months, and at six months. This report presents the three-month results of the first 59 consecutive randomized subjects. At three months, bleeding on probing (BOP) was lower in the NSPT + Lumoral ® -group than in the NSPT group ( p = 0.045), and more patients in the NSPT + Lumoral ® -group had their BOP below 10% (54% vs. 22%, respectively, p = 0.008). In addition, patients in the NSPT + Lumoral ® -group improved their oral hygiene by visible-plaque-index ( p = 0.0003), while the NSPT group showed no statistical improvement compared to the baseline. Both groups significantly reduced the number of deep periodontal pockets, but more patients with a reduction in their deep pocket number were found in the NSPT + Lumoral ® group (92% vs. 63%, p = 0.02). Patients whose number of deep pockets was reduced by 50% or more were also more frequent in the NSPT + Lumoral ® -group (71% vs. 33%, p = 0.01). Patients with initially less than ten deep pockets had fewer deep pockets at the three-month follow-up in the Lumoral ® group ( p = 0.01). In conclusion, adjunctive use of Lumoral ® in NSPT results in improved treatment outcomes at three months post-therapy.